Contraction joint



Oct.

111927' T. DE LA MARE CONTRACTION JOINT Filed April 17. 1925 @MMX Hawai@ atte: nog,

Patented Oct. 1l, 1927.

UNITED STATES PATENT, oFFlcu.

THOMAS DE LA MARE, OF TOOELE, UTAH, ASSIGNOR TO PERCY F. MGKENDRICK, 0F GARFIELD, UTAH.

CONTRACTION JOINT.

Application filed April 17, 1925.

My invention relates to concrete construction and has for its purpose to provide a reinforced contraction joint whereby the eX- pansion and contraction Aof concrete may be allowed for. rlhese objects I accomplish with the device illustrated in the accompanying drawings in which similar letters and numerals of reference indicate like parts throughout the several figures.

In the drawings in which I have illustrated the best and most substantial embodiment of my invention, Figure l is a vertical section through a piece of road or concrete pavement showing the joint therein to allow for expansion and contraction. Figure 2 is a side elevation of a reinforcing member used in such work. Figure 3 is a side elevation, and Figure t an end elevation of a portion of my device. Figure 5 is a transverse. section of a concrete pipe surrounding a wood-stave pipe in which my invention is used at the longitudinal joint of the concrete when pouring the concrete.

In constructing cement concrete around a pipe, the concrete is poured in a plastic'condition and when the concrete sets around the pipe there will be a contraction first of the concrete and more on the surface and eX- posed parts of the concrete than the inner portions thereof, and, invariably, unless some expansion and contraction is provided for, the concrete will crack. In constructing pavements and roads of cement concrete, the upper and exposed face of the concrete will contract and expand, due to changes of temperature, more than the base, so that to prevent irregular cracks it has been the practice to leave an open space at certain distances in the pavements to allow for contraction and expansion. With my device I provide a construction and joint whereby contraction of the concrete around a pipe or in a pavement, due to the setting of the concrete and changes of temperature, will be provided for and prevented from cracking the concrete by my invention, which consists of a V-shaped trough A, positioned across the pavement at distances of about- 10 feet. Said V-shaped trough A has perfo-s rations through its side walls to receive reinforcing wires B. The upper edges of said V-shaped trough are curved outwardly and downwardly and are to be imbedded in the Serial No. 23,841.

concrete. Through said outwardly projecting portions of said V-shaped metal trough, perforations are provided to be engaged by reinforcing wires 3, which are also imbedded in the concrete when poured. In order that the workmen will not fill the interior of said V-shaped metal trough D, when pouring the concrete, I provide a detachable V-shaped trough D with its lower end resting on said reinforcing wires B and filling the space between the sloping sides of the first-mentioned trough A and projecting above the face of the pavement to be laid and after said concrete has been poured to the desired thickness and the surface smoothed or finished as desired, the detachable metal trough l) is to be removed and the contraction joint is filled with plastic asphalt before the pavement is used.

The same general construction is carried out and the same devices used therein when pouring cement concrete around a woodstave or metal pipe, as shown at E in Figure 5. rIhe metal troughs for such use are placed on the upper side of the pipe to be repaired with the reinforcing wires 3, spaced from and surrounding the ,metal pipe, preferably near the surface of the said concrete when finished. The troughs are longitudinally placed in reference to the pipe E and the reinforcing wires 2 contact at their ends i with said pipe. The detachable trough D is used only while the concrete is being poured to prevent plastic material from entering the metal trough A. Then the joint is filled with plastic asphalt.

Having thus described my invention I desire to secure by Letters Patent and claim:

A joint in concrete construction consisting of a layer of cement; V-shaped reinforcing members, running therethrough, having perforations through the side walls thereof and having its upper endscurved outwardly and perforated; reinforcing wires passed through the perforations in the side walls of said trough and imbedded in said cement; and other wires passed through the curved portions of said trough and imbedded in said concrete.

In testimony whereof I have affixed my signature.

THOMAS DE LA MARE. 

